Only the most hardcore Harry Potter fans will remember "The Life and Lies of Albus Dumbledore," a biography of the Hogwarts headmaster mentioned in "Harry Potter and the Deathly Hallows."

For J.K. Rowling, it was essential.

In the plot of the Harry Potter series, the book is relatively unimportant. It's a critical hit piece on Albus Dumbledore, written by gossip reporter Rita Skeeter three weeks after his death. It's a best-seller in the Harry Potter universe, turning the author from a merely a gadfly to becoming one of the series' bad guys.

In the movies, "The Life and Lies of Albus Dumbledore" pops up in "Harry Potter and the Deathly Hallows: Part 1." Hermione grabs a copy to learn more about about Dumbledore's past, leading her, Harry, and Ron to information that eventually helps them defeat Voldemort.

The cover of "The Life and Lies of Albus Dumbledore" in "Harry Potter and the Deathly Hallows: Part 1."Warner Bros.Even though it's there just in passing, Rowling paid close attention to the look and feel of the prop. According to The Wall Street Journal, she wanted the cover "to look like a trashy airport novel." Which is perfect. In the movies, the book does look exactly like an overwritten, disreputable biography that's been dashed off by a gossip columnist in just three weeks. The design also looks a lot like some of the other books and newspapers in the Harry Potter universe, with the overwrought lettering in the title and the framing of Michael Gambon's face on the cover.

This kind of insane attention to detail is very much in character for Rowling.

"She knows exactly what she's doing and what she wants," says Miraphora Mina, the co-owner of Mina Lima, a props company that Rowling works with frequently.

Lately, Rowling has been expanding that detail-oriented style into new endeavors.

Since Rowling wrapped up the "Harry Potter and the Deathly Hallows" book in 2007, she's increasingly put her own stamp on her fantasy empire.

And on a business level, she's putting her stamp on everything as well. She got special deals with Apple and Amazon for Harry Potter ebook and audiobooks. She's orchestrating the rollout of "Harry Potter and the Cursed Child." And she's closely involved in merchandising decisions. It's very much like what George Lucas did for "Star Wars," except Rowling is actually good.